I had a really good, but dull, greenish-brown patina on my Copper Penny, and I finally got tired of looking at it... It just looked "dirty" and grungy, and had that old penny smell (yuk). I polished it really well with Mother's Fine-metal polish, and restored it's shiny "new penny" look (and smell). Now, after sitting on the shelf for a month, it has a beautiful reddish hue to it!
I've never been one to force patina on any brass, bronze, or copper... I think a natural evolution just looks more... well... "natural", lol.